Cigarette smoking remains the single largest preventable cause of premature death and disability in the United States, and designing more effective antismoking campaigns requires an empirical understanding of the natural history of smoking and its determinants. The proposed research extends our ongoing cohortsequential study of smoking from adolescence into early midlife (ages 34-43). Cohorts of 6th-12th graders (N=8,521) were followed annually between 1980-1983 to prospectively predict adolescent smoking transitions with social psychological models. Follow-ups were conducted in 1987-1988, 1993-1994, and 1999-2002 (seven measurement waves with 71% -73% retention of the total sample at each wave), and a parent-child study of intergenerational transmission (N=556 families) was initiated in the last project period. The proposed studies combine an 8th measurement of our total sample using a mailed survey with short-term (18-month) longitudinal studies of targeted subgroups using web-based and mailed survey methods. [unreadable] [unreadable] There are three sets of aims. First, we will embed smoking in its developmental context by studying multiple trajectories of smoking and smoking-related beliefs from adolescence to early midlife, and by relating smoking to the unique hallmarks of early midlife as a developmental period. Second, we will apply innovative theory and methods from cognitive social psychology to examine the role of implicit attitudes toward smoking and attitudinal ambivalence in prospectively predicting smoking initiation, cessation, and relapse. Third, we will extend our work on the intergenerational transmission of smoking to examine the role of parental smoking- specific socialization in prospectively predicting smoking onset. We will also identify predictors of this socialization, with particular interest in the role of parental smoking as it interacts with implicit attitudes and attitudinal ambivalence. The results will be important for tailoring smoking cessation messages aimed at midlife adults, and for improving family-based smoking prevention programs that aim to modify smoking-specific parenting. [unreadable] [unreadable]